Heating and Bending Acrylic Jewellery
I will attempt to explain in very basic terms how to heat and bend acrylic.
Disclaimer: DO NOT TRY this at home. This is purely just my explanation of the process.
These techniques can also be used on acrylic for purposes other than jewellery.The first thing we need to discuss is the necessary equipment needed and responsible personal safety.
I use a standard table top mini oven, the internal size is approx. 40cm / 18in inside
and it is plug and play. You do not need any fancy ovens as long as it reaches a temperature of 180-200 celsius you are in the right heat zone.
YI use a pizza stone or steel which will work fine but they can get too hot and they are not as flat as a baking tray, I like to use a non stick aluminium baking tray that has a bubble design meaning the tray is double sided with an air gap which causes a more even heat distribution.
I try to use gloves that offer me a combination of heat resistance but also are thin
enough to be able to work unimpeded, what I mean by this is as an artist I want to feel my way around my pieces and bending acrylic is as much about technique as it is about gut feelings.
I use tools to help me shape most of my components and pieces. The most used
tool in my arsenal is a dessert spoon, but I also use a knife, a sharpie pen lid and then a myriad of very specific templates and 2 piece molds. I have also designed and used clamp style fold over molds which we can elaborate on in a later post on molds etc.
A mask should be used at all times when using acrylic as it can and will leach toxic
fumes if cut including heating the acrylic, although to a much lesser degree.
PS.I’ll let you all in on a little known secret, every Orchid I have ever made was done so with my old breakfast spoon I had in the workshop, one early morning I was so eager to bend that first Orchid petal shape that I realised I did not have something to bend my really hot acrylic shape with, looking frantically around I focussed on my spoon in my cereal! I quickly wipe on my sleeve and viola!
The perfect tool presented itself at the perfect time. Please note that you are heating a material to between 180-200’ celsius which is extremely hot and can potentially be harmful.
First Step is to place the oven in a safe place and to turn it on, a kitchen oven can be used but bear in mind that the acrylic will leach some toxic fumes so a small cheap oven specifically to heat acrylic is a better option.
Best to use oven that has both a top and bottom element as you want an even distribution of heat in the space, so make sure to set it with both elements on and to a temperature setting of 180’ for 3mm acrylic and 200-220’ for 5mm acrylic.
If 3mm acrylic is being used then a temp of 180 is perfect, for 5mm a little hotter internal temp is required for the extra thickness but it will also need to heat a little longer.
Before throwing a piece of acrylic to be bent in the oven, the the protective layers on both sides must be peeled off.. Jewellery sized pieces will take between 30-60 seconds to heat up enough to bend and shape, larger pieces or thicker pieces will take a little longer but not much more.
I tend to check the acrylic at regular intervals because we are really talking about zones ofmalleability which also require the careful consideration of how much bending needs to be done.
What I mean by this is the hotter the acrylic is the more malleable and longer it will remain in that heated state of malleability, therefore you can work with it longer but that also means that it will bounce back to flat sheet whereas a not so heated piece will hold the bent shape far more than the really hot piece.
Once the piece of acrylic is heated to desired temp/malleability take it out and shape it, be this with a spoon for curved and concave surfaces or across a mold of your choosing.
Once the acrylic has cooled and held the shape you can then remove it from the mold and simply place it aside to cool completely.
There are a few other things to consider when heating acrylic and I will
try to cover those now.
I found out when making the Orchids that if I did not leave the paint in my petal details to dry for at least 3 days then that paint, deep down below the surface which still is not dry will bubble up and spoil the surface once it has been sitting heating up in the oven.
This will often spoil the piece completely so must be considered.
Other things to consider is that it is actually very hard to damage the acrylic by heat, of course leaving it in the oven for much longer than is necessary will eventually break it down but for the most part the acrylic becomes quite rubbery however those very glossy surfaces are very prone to taking on the most subtle of imperfections which is why I suggest using a flat non stick tray to heat as opposed to a pizza stone.
I think that covers most things but I am sure people will have questions so if you want to ask me something you can follow me on instagram
and I will be able to answer questions personally for you.
by Anthony Taylor